(Source : http://www.gurmat.info)
Humayun was the only son of Babur, who was the king of Delhi. When Babur died, Humayun became the king. He was lazy and weak. So one of his officers, named Sher Shah, rose against him. There was a battle in which Humayun was defeated and Sher Shah became the king of Delhi. Humayun had to run away to save his life. On his way to Lahore, he had to pass by Khadur, where Guru Angad Sahib Ji lived. He wanted to become king once again, so he went to Khadur to see the Guru and ask for his blessing.
When Humayun reached the Guru's house, Guru Angad Dev ji was busy teaching students. Therefore, he did not notice the king. The king was upset. He did not like waiting. He thought "How dare the Guru not show any respect to the King!" This feeling made him very angry. In a fit of anger, he drew out his sword to kill the Guru. In the meantime the Guru had finished his prayers and was ready to listen to the king. Seeing what the king was about to do, he smiled and said, "You are brave enough to draw your sword to kill or frighten the peace-loving people. Why didn't you use it in the battlefield, from which you come running like a coward? Your sword did not work in the battlefield, but now suddenly you seem to have become a brave fighter." Humayun felt ashamed. He begged the Guru's pardon.
"I am very sorry, sir," he said, "I really lost my head. You know that Guru Nanak was kind enough to bless my father, who became the king of Delhi. I am no good, because I've lost the throne to Sher Shah. Your blessing alone can make me the king once again. Please have mercy on me and bless me."
The Guru kept quiet for some time. "My blessing has no magic,' he said smilingly. 'To be a king means to be kind, just and helpful to the people. If you promise to do that, you will be a king with God's grace. Be patient and always remember God, who grants all wishes." Humayun hurried away to Persia determined to act upon the Guru's Advice.
After a few years, he gathered his soldiers and also received help from the king of Persia. He came back to India with a very large army and this time, he and his soldiers fought very bravely. Humayun won the battle and became the king of Delhi once again. Humayun was full of gratitude towards the Guru and he wanted to do him a favour, but by that time Guru Angad Sahib Ji had left the human body. Guru Amar Das ji had become the third Guru of the Sikhs. The Guru sent a message reminding the king to be kind and good to his people and to respect holy men. Sometime later, Akbar, the son of Humayun, visited Guru Amar Das ji and offered help for the Guru's Langar.
"The Lord can make the blind see clearly; He treats Man as He knows him, no matter what one may say. Where the truth is not seen, know that pride is strong there. Nanak, how shall a man buy anything if he likes it not." -(Guru Angad Dev ji)